This invention relates to food production. More particularly this invention relates to a method and an associated apparatus for manufacturing a foodstuff such as a frankfurter or wurst.
In the United States food industry, cost containment is a major concern. With the sheer volume of goods produced each year, a fraction of a penny saved per pound or piece may translate into millions of dollars of additional income each year for meat packers or produce suppliers.
One example of this concept is in the manufacture of frankfurters, bratwurst or knockwurst. To manufacture these items, meat packers will chop and whip beef or other meat cuts such as chicken, turkey or pork. Spices will be added along with water, preservatives and coloring to the mix. The resulting semi-solid emulsion or particulate meat mixture will be extruded into a casing of either plastic or edible gut and formed into the familiar shape of a hot dog. After extruding and shaping, the product will be cooked fully so that the customer needs only to heat it thoroughly for final preparation.
Most households in the U.S. today prefer frankfurters to be skinless, that is, without a casing which must be removed before frankfurter consumption. In the preparation of skinless franks or wursts, the processor must remove the skin before final packaging in vacuum-sealed plastic bags. This process involves the physical stripping of the casing by hand or machine and discarding the used plastic wrap.
The cost of the plastic wrap, the personnel needed for stripping and the solid waste removal costs can be substantial. One facility has estimated a $5 million dollar per year revenue increase if this cost could be eliminated. And this estimate does not take the front office, purchasing and machinery capital costs into account.
However, simply eliminating the casing step is not possible because the hot dog must be formed and held together before and during the cooking step. Otherwise, the emulsion will not hold its shape and the product will be ruined. Therefore, a method of creating a stable shape and product containment during this handling must be found. This method must lend itself to high speed production techniques and not alter the taste and look of the product as well.
Although the concept of creating frankfurters or wursts without a casing has been well documented in prior art patents, most of these techniques have centered upon using standard heating platens or molds to create a skin on the product before final processing. These techniques have not been met with widespread acceptance since conductive or convective heat energy is expensive. When a platen is heated, much heat is lost to the surrounding environment or through conduction to the rest of the metallic apparatus. In addition, creating a skin by such methods is time consuming, thereby reducing the production throughput or requiring significant investment in capital equipment to keep output rates high. Accordingly, it would be advantageous to have a an efficient method of partial cooking or processing of hot dog feed stock, in order to form a skin thereon.